The primary objective of this research project is to determine the effects of nutrition on the lipid composition of bone, bone marrow, enamel, dentine and gingiva. This objective will be achieved by studying the following factors: (1) the influence of age, (2) the influence of high CHO diet as against the influence of high fat and high protein, (3) the influence of dietary restriction and (4) the effects of unsaturation of food fats. These studies will be conducted on rats and rabbits. It is expected that the results will be helpful in the design of the future protocol for the study of lipid metabolism in bone, bone marrow, enamel, dentine and gingiva of animals suffering from various metabolic and nutritional diseases (diabetes, protein-malnutrition, obesity, osteoporosis, gingivitis, asceptic necrosis).